This invention is directed to a stove capable of burning a variety of carbonaceous fuel. The stove is completely self-contained and requires no blowers or the like, and thus is suitable for emergency use, outdoor use and for use in societies not supplied with the more convenient forms of energy. The stove includes a vertically oriented wall which serves both as a combustion chamber and a heat exchanger for preheating combustion air.
Man's use of fire dates to antiquity; however, this use has not always been effective and efficient use of the fuel sources available to him. With the invention of the chimney man was able to more effectively control both the rate of burning and the direction of heat output of his fire. With the advent of a forced draft, man was better able to control the efficiency of his fire. The chimney, however, requires a fixed fireplace which is generally totally immobile. Forced draft requires expenditure of some sort of energy to drive the blower whether it be human muscle powered as with a bellows, or electrical energy as with a fan.
In certain emergency situations such as the total loss of any utility service, airplane crashes and the like, the availability of the chimney or forced draft is totally precluded. Further, in certain areas of the world which bear the burden of a very large population and little or dwindling natural biomass resources, fuel is a very precious commodity which cannot afford to be wasted or used inefficiently. Along with a shortage of biomass fuel these same areas suffer from a lack of any central utility service for supplying electrical or petroleum based fuels more commonly found in the industrialized countries.
The cast iron stove, such as the Franklin stove, served the needs of the industrialized countries prior to the industrial revolution. Unfortunately the lack of natural resources or the lack of energy to utilize natural resources prevent the utilization of cast iron stoves in most of the third World countries at this time. Additionally such stoves are quite heavy and therefore not portable, and would not serve the needs as an emergency stove nor a stove suitable for camping and the like.
In the industrialized countries of the world modern portable stoves rely on either the use of cylinders of compressed gas, or fuel delivery systems which require pumps and the like to create an internal pressure within a fuel reservoir. These stoves suffer from several defects including the economics of the system, the complexity of the systems, and the requirement for very specific fuels. As such, they are totally unsuitable for use in less developed countries or use in those situations where very specific fuels are not available.
It is evident from the above discussion that there exists a need for an efficient stove which requires no chimney, no use of any forced draft appliances, can burn a variety of carbonaceous fuels, and is small, lightweight, portable and extremely simple in manufacture and operation.